Draft gear



Nov. 26, 1929. c. H, ToMLlNsoN 1,736,947

DRAFT GEAR Filed June 1e, 1925 "2 sheets-sneer 1 a Chroma" Nov. 26, 1929. c. H. ToMLlNsoN DRAFT GEARv Filed June 1e, 1925 2 sheets-sneer NYS n mw i Patented Nov. 2.6, 1929 UNITED STATES PATNT orrics CHARLES H. TOMLINSON, OF MANSFIELD, OHIO, .ASSIGNOR TO THE TOMLINSON COU- PLER COMPANY, F MANSFIELD,

DRAFT Application led June 16,

My invention relates to draft gears in connection with car couplers and has particular reference to a draft gear in which a liquid is used to control or assist in controlling the relative movements of the parts composing the draft gear.

The object of my invention is to provide a draft gear in which the spring ordinarily employed to regulate the movement of the draft gear parts is assisted in resisting the movement of said parts from a normal posi tion, but in which its action is retarded in a return movement of the draft gear parts to normal position, and my invention resides in the new and novel construction, com* bination and relation of the various parts composing my invention and hereinafter fully described and shown in the drawings accompanying this specification.

In the accompanying drawing:

Fig. 1 is a top plan view of my invention shown as secured to the under sills of a car. A

Fig. 2 is a sectional View of my invention taken on the line 2 2 of Fig. 1 and shows the parts of my invention in normal position relative to each other.

Fig. 3 is a sectional view of my invention taken on the line 2 2 of Fig. 1, but showing- 3o the relative position of the parts the instant two cars are bumped together, or when one car is pushing another.

Fig. i is a sectional view similar te Fig. 3, but showing the relation of the parts when the control spring is under tension due to one car pulling another under load.

Fig. 5 is a sectional view of Fig. 1 on the line 5 5.

Fig. 6 is a full sectional view on the line 6 6 of Fig. 2.

In Fig. 1 I have shown two Linder carsills 1 1 and theseare shown in full in Fig. 5. These sills form a substantial part of the car body and, therefore, provide a convenient means for securing the car coupler and its draft gear to the car body. Mounted between the sills 1 1 is the draft gear as shown in Figs. 1 and 5. The draft gear proper comprises a. cylindrical member 50 2 which is provided with a chamber 3. The

OHIO, A CORPORATION OF OHIO GEAR 1925. Serial No. 37,492.

member 2 is positioned between the sills 1 -1 and is held against longitudinal movement by means of the braced stop members 4 and 4 which are secured to the sills 1 by means of the rivets 5. Encircling the cylindrical member 2 and movable relatively thereto in a longitudinal direction is a yoke member 6. The draft gear as a whole is supported between the under sills 1 1 by means of the cross bars 7 7 which are provided with a pocket 8 in which rests the lower portion of the yoke member 6. The support member 7 is secured to the sills 1 1 by means .of bolts and nuts 9.

The yoke member 6 is provided at one end with a heavy connecting portion 10 and inwardly, but separately formed, projects a cylindrically shaped plunger 11 which has a still smaller plunger 12 withthe shoulder 13 formed therebetween. The member 2 has an end enclosing portion 1li through which is provided an opening to receive the stem 11. Surrounding the stem 11 and having a threaded engagement with the member 2 is a collar 15 provided with a U-shaped packing 16 to prevent leakage from the chamber Jalong the'surface of the stem 11. Around the face of the collar 15 are cavities 17 for the application of a spanner wrench in manipulating the collar 15. y

At the opposite end of the yoke 6 from Jthe member 10 is a hollow member 18 in which. is positioned the end of a coupler head stem 19 and which is locked to the member 18 by means of the key 20. The key 2O is also shown as passing through the under sills 1 1 and slots are provided therein for this purpose, but the slots are sufliciently long to permit relative movement of the yoke member 6 in a longitudinal direction.

Projecting inwardly from the member 19 is a separately formed stem 21 and projecting inwardly from the stem 21 is a part 22 which has a face shown as hutting against the face of the stem 12. It will be seen that there is no lost motion between the plungers or between the plungers and the yoke mem-v ber and that they must all move in unison. Between the stems 21 and 22 is formed a shoulder 23. Positioned within the end of le@ (ilV the member 2 and having a screw threaded engagement therewith is a collar 24 having a passage to receive the stem 23. Also positioned in the end of the member 2 is a collar 25 having a screw threaded engagement therewith and which is provided with a packing 26 and holes therein 27 to receive a spanner wrench in adjusting the collar 25. The paclring 26 will preventrleakage of liquid from the interior of the member 2 to the exterior along the surface of the stem 2l.

Positioned upon each stem l2 and 22 is a collar 28 and 29 respectively. These collars malre a reasonably close tit with the inner surface of the member 2, but there is a considerable space between the collar and the surface of the stems l2 and 22 and these spaces are designated as 30 `and 3l respectively. rlhe collars 28 and 29 are shown as abutting against the shoulders 32 and 33 respectively as well as against the shoulders 13 and 23 upon the stems 1l and 2l respectively. Positioned between the collars 23 and 29 is a friction spring S comprising the outer and inner members 34 and 35 and the surface of these members bind together with increasing friction as the collars are moved toward each other, or in other words, as the compression of the spring S increases. rIhe spring S, itV will be observed, tends to normally maintain the collars 23 and 29 at their extreme spaced position and since the construction is such that the shoulders 13 and 32 and 23 anc 33 practically coincide, the parts 2 and 6 will` be normaily held in a predetermined relation, as 'shown in Fig. 2, through the action of the spring S.

A construction as above described will in itself perform the functions of a draft gear as is common practice, but if the parts 2 and 9 are moved relative to each otherin either direction andthe compression of the spring S is increased thereby then when the exterior stress,- Which is maintaining the spring S under increased compression, is removed, the

parts will tend to return to normal through the stored up energy in the spring S` very quickly, and this'is quite perceptible where the mechanism used in connection with passenger coaches, andit is my desire to do away with this sudden retnrn of the parts to normal under the action of the spring S and thereby avoid annoyance to the passengers, and to do this I fill thechamber 3 with a liquid, which may be water, oil, glycerine or any other liquid. which, is' suitable to meet the requirements and conditions. It` will be apparent that if the chamber 3 is :filled with a liquid that if the collars 28 and 29 are suddenly moved toward each other that the liq` uid would tend to be compressed in the chamber 3 and resist the movement of the collars toward each other, but that this resistance may be decreased if a Way is found of permitting the escape of the liquid from' the chamber 3 during the relative movement of the collars 23 and 29. By referring to Fig. 3, it will be noted that there is a cavity 36 therein which is not present in Fig. 2 and also a cavity 37, therefore, if the liquid contained in the chamber 3 can bepermitted to escape into the cavities 36 and 37, which are formed at the instant of and simultaneously with the movement of the collars 28 and 29 toward each other, then the resistance to their movement will be decreased, depending upon the rate at which the liquid escapes from the chamber 3 into the cavities 36 and 37. The spaces 30 and 3l between the collars and the stem constitute passages between the chamber 3 and the cavities 36 and 37. By increasing the size of the I'Jassages 30 and 3l the rate of flow of the liquid from the chamber 3 into the cavities 36 and 37 will, of course, be proportionately greater and the resistance to the movement of the collars 28 and 29 toward each other will be proportionately decrease-d.

TWhen the stress which is moving the member 6 in the direction of the arrow, as shown in Fig. 3, is relieved under normal conditions the spring` S would return the member V6 to its normal position relative to the member 2, but where the chamber 3 has under normal conditions been lilled with a liquid and hence the members 36 and 37 'are iilled with this iiqnid, thev return of the part 6 to its normal position will be much. slower and will, of course, depen-d upon the area ofthe passages between the stems and adjacent collars 23 and 29.

In order to have access from the passage 3l with the cavity 37, as shown in Fig. 3, .the face of the collar 29 adjacent the shoulder 23 is provided with one or more depressions 38; A

If the movement of the member 6 relative to the member 2 is inthe direction of the arrow, as shown in Fig. 4, as would be the case when one car is pulling another, then the relation Aof the parts is reversed, that is, the collar 23 would be toward the collar 29 and the spring S compressed,- butr I would have formed in this case cavities 39 and i0 and the passage30 would be connected with the cavity 39 through the depression 38 in the face washer 28; Y

In order to fill the chamber 3 with a liquid I provide a passage il, which I have shown as closed, by means of a screw plug 42, but in place of this plug there may be substituted a reservoir which may contain a supply of liquid and which will maintain the chamber 3 full of the liquid at all times and with a suiliciently small opening between the re'servoir and the chamber 3 when there is any back pressure upon the liquid vWithin the chamber 3, there will be requireda considerable time element for the liquid to flow from thechamber 3 into the receptacle, which will, therefore, not reduce the pressure in the chamber 3 to any appreciable extent so as to ai'rect results secured by the liquid in the chamber 3 upon the moving parts of the draft gear.

By making the two stems l2 and 22 split it makes a much easier assembling proposition of the parts, a u d also has the advantage that it' pressure is applied to the outer end of the stems 1l or 2l somewhat oil center7 or if the faces of the spring S should not be sulciently parallel, then the stems could adjust themselves to meet vthis condition somewhat by moving relatively to each other at their ad jacent faces, otherwise there might be a tendency to bring` a bending strain upon the members l2 and Q2 if they were united at their adjacent faces and might actually beneL the combined members and produce a permanent set Which would interfere with the otherwise tree operation ot the parts.

rllhere are, of course, modifications Which may be made from the disclosure herein given by those skilled in the art, but l do not wish to be limited other than by my claims.

It vill be observed that I employ only one spring to take care of the return or the parts to their normal position, and that the reaction of this spring is retarded through the use of a liquid With respect to the construction employed and resistance to compr sion of the snring is also assisted through the action or' the liquid Within the chamber 3.

l claim:

l. A draft gear comprising a single chamber member containin a liquid, means to sups port the same on a ear against longitudinal and vertical movement, a yoke shaped member encircling the chamber member longitudinally and movable longitudinally relative thereto in tivo .direct-ions, plunger members butting against the ends or the yoke member and projecting into the opposite ends of the chainber member and having their ends uf'ithin the chamber member engage each other, means surrounding the plunger members to prevent the escape ol the liquid, a single yielding Aunit Within the chamber to normally hold the plungers andyolte member in a predetermined position relative to the chamber member and means Within the chamber member to displace the fluid and the yieldin unit Wh en the voke membe moves longitudinally in ci her direc` tion and prevent the quick return oi 'the parts 'to normal and to create a plurality of auX- iliu chambers to receive the said liquid as the members move longitudiin t 2. A draft gear comprising a member having a single chamber and a yoke member movable relative to each other, means to support the members on a car and prevent movement of the chambered member, a p. ot' pluna'ers projecting Within and Without the chambered member and having thei r inner ends abut each other and movabl longitudinally with the movement ot' the yoke menber, and each plunger having an integral shoulder, a single yielding iriction spring within the chamber between the shoulders to hold the plungers in a predetermined position, fluid pressure means Within the chamber to resist the plungers moving from their predetermined position and to retard the rate of return of the plungers to their predetermined position and a movable end to the chamber to adjust the tension on the spring' and change the capacityof the chamber.

3. A draft gear comprising a pair oi" relatively movable members, a plunger comprising tivo parts having alined aX-es and abutting ends interposed between the members and movable With one member and under a cornpressive torce applied to the ends of the parts .for movement in either direction; and movable relative to one of the members, yielding fluid pressure means confined Within one of the members to resist said relative movement, a 'friction spring to yieldingly resist said relative movement and means to secure the gear to a car body.

4l. A draft gear comprising a ohambered member haviig a chamber therein containing a tluid and a tivo part plunger mounted in the chamber and projecting from each end, means to prevent the leakage of the fluid along the surface of the plrnger parts to the exterior, collars mounted on the plungers to engage shoulders on the plungers and a yield spring positioned between the collars and spreading them apart and leaving a cavity between the collars filled with the lluid, a yoke shaped member engaging the exterior faces of the plunger to move the plunger parts relative to the chamber-ed member and causing simultaneously therewith the relativo movement of the collars thereby creating other cavities Within the chambered member and means connesting the chamber' and the other cavities and providing a retarded iioiv oiC the fluid from the chamber into the other cavities and vice versa.

ln testimony whereof l affix my signature.

CHARLES H. TCMLINSON. 

